Mechanically it's very easy. The skill involved really relates to the judgement-making necessary for safe manoeuvring and the hazard-awareness required for safe 'defensive driving'.
It all depends. It depends on how quick the learner is at picking it up. It depends on how much time the learner can devote to lessons. It depends on how good the instructor is. And then, some people are naturally good drivers, and some are not. Try it, and see how you get on.
I found it very hard to learn at first then it got easier. As Buenchico says, its not the mechanical bit that's hard its the observation, judgement and reacting to situations that is hard.
It's not that difficult to drive a car once you've mastered where everything is - the difficult bit is working out what the morons on the roads are up to
Driving is easy enough, though as Cloverjo says an automatic car (ie very few gear changes) is best. But half a century on, I’m still not great at parking and reversing.
As for the need to cope with other drivers, this comes as your own driving improves so you become more aware of the things others might do, such as “Will he be trying to cut in front of me?”